Philander shaw



P SHAW. HOT AIRIENGINE."

'No." 90,128.. 1 Patented May .1 1869 PHILANDER SHAW; on BOSTON, MASSACHUSETTS, AssIoNoR To 'SHAWS UNION AIR-ENGIN E COMPANY, OF SAME PLACE."

as Patent No. 90,128, dated May 18,1869.

IMIPRO'V'EDEENT IN HOT-AIR ENGTNBS.

The Schedule referred to in these Letters Patent and making part of thosame.

To all ichom concern.

Beit known that I, PHILANDER SHAW, of Boston, in the county of Suffolk, and State. of Massachusetts, have invented certain new and useful Improvements in Hot-Air Engines; and Ldo hereby declare that the following-is afull and exact description thereof, reference being bad to the accompariying drawings, and to theletters of reference marked thereon.

To enable others skilled in the art to make and use my invention, I willproceed to describe its nature, construction, and use.

The nature of my invention consists- First, in the construction and arrangement, as here inafterdcscribed, and further illustrated in the drawings, offth inlet-valve. This valvebeingexposed to great heat', is made in the form of a cylindrical vessel,

intowhich a pipe conducts, "at each stroke of the engine, a current of cool air, w'hich efl'ecting itspurpose, that is, .lowering the temperature of the valve, is free to flow out upward around the outside of saidpipe into the passage into thefurnace- Second, in combination of, the inlet-vacuum valve I with the working-cylindcrof an air-engine.

' Drawings.

Figure 1 is a perspective view of my engine.

- Figure 2 is a plan.

Figure 3 is a horizontal section.

Figure 4 is a vertical section on the line 10 x, fig. 2.

Figure 5 is an elevation showing the valves.

Figure 6 is an elevation, showing the working-cyl' index-s and the auxiliary valves.

S, figs. 3 and 4, represent the furnace, fig. 3 showing it in horizontal section, with a plan of the grate, and fig.- 4in elevation, J representing an inside lining of lire-brick.

These fire-bricks have projections jj, or knobs, made on their: outer side, as shown, thus leaving an air-space between the inner and outer lining, extending entirely aroundthe. furnace, through which the air that enters thefurnacc above the grate flows.

A vA, in all the drawinga is an air-tight casing extending entirely around thefurnace, and, with its top and bottom, forms an air-tight reservoir for compressed air, and includes withinitseli the furnace, the inlet and outlet-valves, and most of the tubes through which most of the air flows.

c, figs. 2, 3,"aud 5, represents the direct draught or a orifice for the escape of the products of combustion when (thefire is first built, but may be closed by means of a door of valve, similar in construction to that shown, when the fire is well started;

I, figs. 1, 2, and 3, represents the asmopcning, which leads directly into the furnace.

Both the ash and fuel-openings have doors that fit air-tight,constructed similar to those shown in the drawings.

H, figs. 1, 2, and 4, represents a fuel receptacle, from which the fuel is fed to the fire, while the engine 13 in action, through the top of the furnace.

The bottom of this fuel-box H is providedwith a sliding bottom or valve, U, .which is operated by the swinging arm U,'fig. 4.

This swinging-arm has a gear out upon its rear end, as shown in the drawings, into which a pinion, P, works. This pinion isoperated by a lever, h;

vBy this arrangement, and by proper manipulation,

which will be understood by inspection of the'drawrugs, it is obvious that the fire may be-replenished with fresh fuel, while there is the requisite pressure within the furnace to operate the engine without reducing this pressure.

The furnace is provided with an opening, a, figs. 3 i and ,4, above the grate, and withgan opening, a, fig. 4,

below the grate, throughwhich air under pressure is supplied, to the furnace.

' The working-cylinders, of which there are two, act,

upou'one rocking-beam.

The cylinders are single-acting, that is, the piston of each is forced upward by admitting the compressed heated air and gases from within the furnace beneath thepiston, both pistons being connected with the rockingdyeam G, by means of the pitman P, figs. 1, 2, and 4, so that the downward movement of each piston is produced by the upward movement of the other acting through the pitmau 1 and the rocking-beam G.

' The cylinders A A aredivided into two sections by" the annular recess B B, figs. 1, 4, and 6.

That part, of the cylinder which is above this space is turned true and polished, sothat the piston-head D In this truck, the connecting-rod or pitman P, figs.

1, 2, and 4, plays, and is connected to the piston head D by a joint, as shown in fig. 4, which is kept-cool by a free exposure to the atmosphere, and by lubrication, for which good facilities are afforded. v,

The trunk passes through the upper head 4, figs. 1, 2, and 4 of-the cylinder, where -it is packed and guided by the gland Z.

The upper cylinden-head is furnished with valve,,.

which, when forced open by the compression of the air in the annularspace between the trunk and the upper section of the cylinder,'permits the said com-- pressed air to pass through the valve-box K, figs. 3 and 4, and pipe L, into-the reservoir around the valves.

, The upper cylinder-head is furnished with a puppetvalve working in the valve-box W,*th"e purpose of which is to open and admit air into the annular pump thebottom of this drum comes very'near to the hottom oi the cylinder, there being always an annular and'end clearance.

The groove or chamber B B, around the cylinder, communicates with thocompressed air in the outlet (pump)-valv e chamber. where it is comparatively pure and cool.

This communication is made by means of the pipe W, figs. 3 and '6, which terminates in the auxiliary valve-box b.

The auxiliary valve-box b, figs. 3 and 6, contains puppet-.valves, opeiated by any suitable mechanism, that shown beinga cam on the main shaft, figs. 2 and 3, acting on the levers d d, figs. 2, B, and 6, and through them upon the valve-stems b b, to open the valve against the pressure of a spring, the reaction of which assists to close it.

It'will be seen that when; one of these valves is open, air will flow into the pipe W, figs. 3 and6, and thence into the annular space B.

If this valve is open, as it should be, after the ex haust-valv'e closes, and before the main inlet-valve opens, all the clearance or unoccupied space in the cylinders and valve-passages will be filled with pure air but little heated, and of density equal to that within the casing and furnace.

The objectof thus introducing air through thepipe Wat this place and time is threefold: first, by renders ing the pressure alike on both sides of the inlet-valve, it is balanced and operated in cqmlibrio, by which. the power necessary to work it is reduced to the minimum; second, by' having the space in the cylinder .filled with pure air, that which rushes in afterward from the, furnace will not be likely to carry the solid products of combustion into the joint or annular space between the finished portions of the cylinders; third, by the introduction of cool compressed air, asdes'cribed, the temperature of the finished parts of the cylinder, and piston which work in contact with each other, are kept sufiiciently. cool' to admit of eflicient lubrication.

figs. 4 and 5, is the inlet-valve, apd corresponds in; the sliding valve on a steam-engine.

This valve is open at the-commencementof the upstroke of the piston, but closes at about three-fourths stroke of the same, or at such a point as will give the best result.

As shown in the drawings, this v'alve V has, besides the disk common to all puppet-valves, a hollow cylinder, extending upward,.so that the valve, as a whole, forms a cylindrical vessel open at the top.

The pipe T, figs. 4 and 5, extends downward in the valve, as shown in the drawings, so that when the en glue is working, acurrent of cool air is sent down from the air-pump, through .L' and T", into said valve a. each stroke of the piston, thus preventing it from being overheated. v

At abodt the time the upward movement of the piston ceases, and after the inlet-valve V has been closed, the exhaustvalve V opens and permits the contents of the cylinder to escape and to be forced out by the descent of the piston into the exhaust-pipe N, figs. 2, 3, 4, and 5.

- The valves shown in the drawings are of the puppet variety, and are operated at all times by cams attached to the shaft N, figs. l, 2, and 4, said shdfit-being operated by the shaft N", figs. 1 and 5, which connects by gears to the main shafi L The throttle-valve p, figs. 4 and 5, situated in the hot air passage L, serves to regulate the speed of the engine, being connected by its valve-stem to the regulator Q, figs. 1, 2, 4, and 5, so that as the speed of the engine increases, the orifice connecting L is more or less closed, thus' checking the fiow of air through the engine until the speed is reduced to its nornial rate. If the engine is going too "slow, the reverse of this action takes place.

V" represents a vacuum-valve, one of which is at tached to each cylinder, near the bottom, and serves to admit air when the engine is started, or whenever, ii'om any reason, a. vacuum occurs in 'the cylinders under the pistons.

In starting a fire on the grate, the main inlet and exhaust-valves-should be opened, as well as the ashpit door, to establish a-draught through the engine by way ofthe. cylinder.

When the fuel is well ignited,'all the doors and valves through which aincan pass to or from the furnace should be closed and made air-tight.

The main shaft of the engine itself may be rotated by suitable means, when the pumps forming part of the engine will supply the air needed in the furnace.

When suincient pressure has been generated to rotate the engine, the extraneous force may be discontinued, as the expansion of the air supplied by the pumps of the engine will continue to increase the pressure within the furnace until the engine has some work applied to it to absorb the power generated What I claim as my invention, and desire to secure lay-Letters Patent of the United States,is

1. The inlet-valve V, when made hollow and combined with the cold-airpipe T, substantially as described.

2. The combination of the inlet-vacuum valve V" with the working-cylinder of the air-engine, substantially as described.

PHILANDER SH Witnesses:

WILLIAM Enson, Jos. R. Ensox. 

